<template>
  <div>
    <h1>当前求和为：{{sum}}</h1>
    <select v-model.number="n">
      <option value="1">1</option>
      <option value="2">2</option>
      <option value="3">3</option>
    </select>
    <button @click="increment">+</button>
    <button @click="decrement">-</button>
    <button @click="incrementOdd">当前求和为奇数再加</button>
    <button @click="incrementWait">等一等再加</button>
  </div>
</template>

<script>
export default {
  // eslint-disable-next-line vue/multi-word-component-names
  name:'Count',
  data() {
    return {
      n:1, //用户选择的数字
      sum:0 //当前的和
    }
  },
  methods: {
    increment(){
      this.sum += this.n
    },
    decrement(){
      this.sum -= this.n
    },
    incrementOdd(){
      if(this.sum % 2){
        this.sum += this.n
      }
    },
    incrementWait(){
      setTimeout(()=>{
        this.sum += this.n
      },500)
    },
  },
}
</script>

<style>
button{
  margin-left: 5px;
}
</style>

